While Peru felt that the matter was already decided in the Ecuadorian–Peruvian War of 1941, Ecuador claimed that the Rio de Janeiro Protocol was not executable because a 78 km section of the border was not precisely defined.
The conflict began on January 22, 1981, the day on which the Peruvian government denounced the attack on one of its aircraft that was carrying out a supply mission destined for border surveillance posts on the Comaina River.
Peruvian President Fernando Belaúnde Terry ordered the inspection of the river until its source located on the eastern side of the Condor range (in Spanish, Cordillera del Cóndor).
[6] The establishment of these posts was considered by the Peruvian Government as a violation of a status quo line arranged between the military leaders of both countries in the course of several meetings at the end of the 1970s.
The conflict, which occurred in a then non-demarcated area of the common border between Ecuador and Peru, ceased with the Ecuadorians being expelled from the slopes and driven back to the summit of the Cordillera del Cóndor.
The Organization of American States (OAS), had to intervene through the Sorrosa-Du Bois Act, setting the location coordinates allowed for border troops, ratifying the condition of the mentioned mountain range as a natural boundary between the two countries.
Known versions after the eviction of the Ecuadorian troops, between January 28 and February 1, 1981, confirm that this frustrated occupation was planned since 1977, when the first clashes between border patrols began to occur.
Levoyer proposed a new plan which placed all personnel, weapons, supplies, etc., in twenty-four hours in the front and ready to fulfill the mission of defense.
The talks took place in the border line near the Pacific Ocean, in the towns of Huaquillas (Ecuador, Province of El Oro) and Aguas Verdes (Peru, Department of Tumbes).
The Marañón River through the Act of Brasilia, closing the border, as indicated in the Protocol of Rio de Janeiro, and declaring the end of all differences between the two nations[14]